极地地区多模GNSS精密单点定位精度分析     

温波  朱庆伟  张俊 《大地测量与地球动力学》2021,41(7):682-689

基于多模全球导航卫星系统（GNSS）与精密单点定位(PPP)技术,分析极地多模GNSS精密单点定位策略。通过一天一站解和一天多站解,对11种不同导航卫星系统组合下的精密单点定位结果进行实验分析。结果表明：1）各组合中BDS和Galileo组合的定位结果最差,与平均值相比定位精度的差值范围在0.4~1.3 cm之间;2）极地地区各组合N方向收敛时间的平均值为7~11 min,定位精度的平均值优于1.3 cm,明显优于E方向和U方向;3）相同环境下三系统组合较双系统组合在E、N、U方向的收敛时间分别缩短10.3%、14.1%、7.3%,在定位精度上分别提升9.6%、4.6%、11.7%;四系统组合较三系统组合在E、N、U方向的收敛时间分别缩短6.8%、－2.1%、2.0%,在定位精度上分别提升4.9%、－7.1%、5.3%。研究结果表明,三系统组合的定位性能较双系统组合提升明显,四系统组合较三系统组合定位性能改善不明显。  相似文献   

Upwelling Process of the Western Himalaya Mountains: Height and Velocity Estimation Evidenced by Formation and Evolution of the Zanda Basin,Tibet,China   总被引：1，自引：1，他引：0  

ZHU Dagang  MENG Xian’gang  SHAO Zhaogang  YANG Chaobin  HAN Jian’en  YU Ji  MENG Qingwei  Lü Rongping 《《地质学报》英文版》2010,84(2):280-295

<正>Based on field geological survey,stratigraphic section measurement and indoor comprehensive investigation,the Zanda Basin's tectonic location in the Himalaya Plate was ascertained,and the formation and evolution of the Zanda Basin during the Pliocene to Early Pleistocene was classified as six stages:(a) primary rift-faulting stage,(b) quick rift-faulting Stage,(c) intensive rift-faulting stage,(d) stasis stage,(e) secondary rift-faulting stage,and(f) secondary quick rift-faulting stage.Based on this six-staged formation-evolution theory of the Zanda Basin,the upwelling process of the Western Himalaya Mountains from the Pliocene to Early Pleistocene was classified as the following five stages:(a) slow upwelling stage(5.4-4.4 Ma),(b) mid-velocity upwelling stage(4.4-3.5 Ma),(c) quick upwelling stage(3.5-3.2 Ma),(d) upwelling-ceasing stage(3.2-2.7 Ma), and(e) quick upwelling stage(2.7 Ma).Research has shown that in the duration from the Early Pliocene(4.7 Ma) to the End of Pliocene(2.67 Ma),which lasted 2.03 million years,the Himalaya Mountains had uplifted 1500 m at a velocity of 0.74 mm/a;this belongs to a mid-velocity upwelling. During the 1.31 million years in the Early Stage of the Early Pleistocene,the Himalaya Mountains had risen up another 1500 m at a velocity of 1.15 mm/a;this is a rather quick upwelling.All of these data have shown that the upwelling of the Western Himalaya Mountains is along a complicated process with multi-stages,multi-velocities,and non-uniformitarian features.  相似文献   

MAGIS集成方案的设计与实现     

邵彩玲  邵宝民  赵清伟  陈戈 《地理空间信息》2009,7(3):99-102

在对时空分析复杂性分析的基础上，重点研究MAGIS和订单服务模式的特点，借助于多线程、Web Service及Batch处理技术，制定了一套以订单和时空分析为中心的新的集成方案。  相似文献   

新疆北斗卫星地基增强系统性能测试及分析     

孟庆伟  蒲莉莉 《测绘与空间地理信息》2021,44(z1):58-61,64

为探究和验证在新疆整体地形局限、基准站建设密度不均情况下的新疆北斗卫星地基增强系统(XJ-CORS)的定位精度、解算能力及系统性能,本文首次以新疆全域为测试范围,对实时定位和静态定位精度所涉及的初始化时间和固定率、事后高精度定位性能、时间可用性、空间可用性、兼容性等指标,以及基准站管理、流动站管理、差分数据格式支持、自动运行能力等进行系统全方位测试.测试结果证明,XJ-CORS可为新疆全域用户提供北斗系统米级、亚米级的差分导航定位服务和实时厘米级高精度定位服务.  相似文献   

山东耕地生态保护存在的问题及对策     

王增如  许庆福  乔庆伟 《山东国土资源》2007,23(8):12-14,17

山东省作为一个粮食产销大省,国家的粮食主产区之一,搞好耕地保护十分重要。耕地生态保护是耕地保护的重要组成部分,是实现农业可持续发展的前提条件。从分析全省耕地数量及特点入手,阐述耕地生态环境存在的主要问题,针对存在的问题,提出耕地生态保护的对策。  相似文献   

Grey-relation Analysis of Traffic System and Urbanization in Jilin Province of China     

XIANG Wei  WANG Yu  LI Ning  ZHU Qingwei 《中国地理科学(英文版)》2007,17(3):216-221

It has been long believed there should be some relations between traffic system and urbanization,but the in-teraction between them,especially on the regional level,has been not in consideration due to the difficulty in quantitative analysis.Based on the development of Jilin Province during 1981-2003,the paper analyzed the relation with the grey-relation model which was adjusted to fit specific problem,and came to some conclusions.Firstly,there exists ob-vious and strong correlation between traffic system and urbanization.Secondly,urbanization responds to the develop-ment of traffic system mainly on the level of urbanization,such as population and developed area,however,less on urbanization quality.Thirdly,traffic system influences urbanization as a whole except for several peculiar factors,which means we should optimize the whole traffic system to promote urbanization.Based on those conclusions,the paper illustrated the mechanism of traffic system,promoting urbanization scale and urbanization quality.  相似文献   

豫北平原地下水与地表水联合调度初探   总被引：3，自引：0，他引：3  

孟庆伟  刘继朝  苗长军  张和军 《地下水》2004,26(4):232-235

水既是重要的自然资源,又是重要的自然环境要素,是可持续发展的基础与条件,是环境问题与发展问题的核心.本文论述了豫北平原地表水和地下水联合调度的必要性及其理论基础;分析了利用地下水库蓄洪的可行性和技术思路,探讨了可能产生的生态系统平衡、调水随机性及泥砂问题;提出了豫北平原联合调度科学利用水资源的一些措施.  相似文献   

Enlightenment of the Mariana Fore-arc Sedimentary Basin Evolution to the Subduction Process     

XING Lei  LI Qianqian  MENG Qingwei  LIU Huaishan  WEI Ji  Lü Boran  ZHOU Heng 《《地质学报》英文版》2022,96(1):71-80

The Mariana subduction structure is a hot topic in ocean-ocean subduction zone research,and its subduction mechanism has attracted wide attention from experts and scholars in China and abroad.Based on the multi-channel seismic data of survey line MGL1204 in the Mariana fore-arc and DSDP ocean drilling data,this paper studies the development and evolution characteristics of the structure and strata in the Cenozoic Mariana fore-arc sedimentary basin.The Cenozoic strata are divided into six seismic sequences,with the possible era of each seismic sequence discerned,and the relationship between fault development and earthquakes analyzed.The episodic activity of the volcanic chain of the Mariana island arc is thought to control the tectonic and stratigraphic development pattern of the Cenozoic sedimentary basin in the fore-arc.Between 16°N-19°N and 146°E-151°E,the maximum thickness of the sedimentary center of the Cenozoic fore-arc sedimentary basin in Mariana is about 2360 m.Normal faults are developed in the area and some broke to the seabed,indicating that the Mariana island arc is still in the post-arc expansion stage.The application of multi-channel seismic sections in structural and stratigraphic evolution study is an important means to elucidating the Mariana subduction mechanism.  相似文献   

济南市华山湖开挖建设渗漏分析研究          下载免费PDF全文

宿庆伟  姜巧巧  耿付强 《山东国土资源》2018,34(12)

该文在查明区域水文地质条件、湖区地下水的类型、分布、埋藏条件、含水层及隔水层特征、岩性结构以及地下水的补给、径流、排泄条件的基础上,通过现场试验,确定了天然状态下湖区各含水层之间的水力联系、黄河侧渗补给量及湖区向小清河的排泄量,结合数值模拟,预测了湖区维持设计蓄水位21.5m时黄河的侧渗补给量、湖区向小清河的排泄量及湖区对周边地下水位的影响。结果表明,天然状态下,黄河侧渗补给量为748.23m~3/d,湖区向小清河排泄量大约为52.03m~3/d,黄河侧渗补给量远大于湖区向小清河的排泄量。数值模拟结果表明,湖区维持设计蓄水位21.5m时,不同水文年湖区接受的侧渗补给量均大于湖区的渗漏量,且对周围地下水位的影响不超过1.5m,因此,湖区维持设计蓄水位21.5m时可不考虑防渗措施。  相似文献   

城市公共交通覆盖度空间统计分析研究     

孟庆伟 《测绘与空间地理信息》2020,(3):141-145

为了合理分析城市公共交通发展现状并对其发展提供可参考的依据,本文利用地理信息系统空间分析和统计方法,在确立多个评价指标的基础上,对城市公共交通覆盖度情况进行不同角度、不同方面的评价。以沈阳市内部分区域为研究对象,提取研究区域基础地理数据,结合人口数据以及公共交通线网缓冲区,选取城市主次干道为边界划分分析单元,将人口密度与道路数据相结合,将评价体系与数据进行对比分析。根据评价指标,得到研究范围内城市公交资源的分布状况。实验结果表明,该方法能够较好地分析城市公共交通分布特征,为城市交通规划设计提供思路。  相似文献